JP2020067007A - Electrically-driven supercharger - Google Patents

Abstract

To provide an electrically-driven supercharger capable of simplifying a constitution for supplying a lubricant to a bearing.SOLUTION: An electrically-driven supercharger 10 includes an oil supply flow channel 44, and includes oil supply holes 38 positioned at upper parts of coil ends 25e, 25f. The electrically-driven supercharger 10 includes oil supply members 50a, 50b inside of a housing 11. The oil supply members 50a, 50b respectively have main body portions 55 positioned at a radial inner side with respect to outer peripheral surfaces of the coil ends 25e, 25f on a position at an upper side in a vertical direction with respect to a rotating shaft 20. The oil supply members 50a, 50b have oil guide portions 56 extended from the main body portions 55 to bearings 31, 32 side disposed at a side separating from tip end portions of the coil ends 25e, 25f, from a position of the tip end portions of the coil ends 25e, 25f in an axial direction of the rotating shaft 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric supercharger.

  For example, as described in Patent Document 1, the housing of the electric supercharger is provided with a lubricating oil supply port and a lubricating oil passage communicating with the lubricating oil supply port. Further, the housing is provided with an introduction passage for guiding the lubricating oil supplied to the lubricating oil passage to the bearing and the coil end of the electric motor. Then, the lubricating oil supplied from the supply port to the lubricating oil passage is guided to the bearing and the coil end by the introduction passage, so that the bearing and the coil end are cooled.

U.S. Patent Application Publication No. 2014/0056726

  However, in Patent Document 1, the introduction passage for supplying the lubricating oil to the bearing is provided by separately forming a passage extending from the lubricating oil passage to the thickness of the housing and a passage connecting the passage and the bearing. ing. Therefore, it is necessary to process the housing a plurality of times to form the introduction passage, which complicates the configuration for supplying the lubricating oil to the bearing.

  An object of the present invention is to provide an electric supercharger that can simplify the configuration for supplying lubricating oil to bearings.

  An electric supercharger for solving the above problems includes a housing, a rotating shaft rotatably supported by the housing via a bearing, and an impeller connected to one end side of the rotating shaft in the axial direction. An electric motor housed in the housing and rotating the rotating shaft, the electric motor comprising a stator core, and coil ends protruding from both end surfaces of the stator core located in the axial direction of the rotating shaft. An electric supercharger comprising a stator having an oil supply passage extending in the axial direction of the rotating shaft in the upper part of the housing, and communicating with the oil supply passage, and the coil end in the vertical direction. An oil supply hole located above the coil shaft, and is arranged radially inward of the outer peripheral surface of the coil end at a position vertically above the rotating shaft. An oil supply having a main body portion and an oil guide portion extending from the main body portion on the bearing side arranged on the side away from the front end portion of the coil end from the position of the front end portion of the coil end in the axial direction of the rotating shaft. The gist is to provide a member.

  According to this, by the oil supply member, the main body is arranged on the upper side in the vertical direction with respect to the rotary shaft, the radial direction inner side of the rotary shaft with respect to the outer peripheral surface of the coil end, and the oil guide portion extending from the main body is provided. The coil end can be arranged so as to extend to the bearing side arranged on the side away from the tip end portion.

  The lubricating oil passes through the oil supply hole from the oil supply passage, falls on the coil end, and is supplied to the coil end. A part of the lubricating oil supplied to the coil end flows along the outer peripheral surface of the coil end and then drops from the outer peripheral surface of the coil end. The oil guide part of the oil supply member is arranged on the bearing side from the position where the lubricating oil falls, that is, on the bearing side with respect to the position of the tip end part of the coil end, and the lubricating oil dropped from the coil end along the outer surface of the oil guide part. Flowing. Then, of the lubricating oil flowing along the outer surface of the oil guide portion, the lubricating oil flowing toward the bearing arranged on the side away from the tip end portion of the coil end along the axial direction of the rotating shaft is supplied to the bearing. , Bearings are lubricated and cooled. Therefore, the structure for supplying the lubricating oil to the bearing can be configured only by installing the oil supply member in the housing, and can be simplified as compared with the case where the passage is formed in the thickness of the housing, for example.

  Further, in the electric supercharger, the bearing is an inner ring fixed to the rotating shaft, an outer ring arranged outside the inner ring, and a rolling element arranged between the inner ring and the outer ring, And the oil guide portion has a tip edge near the bearing arranged on the side away from the tip portion of the coil end, the tip edge of the outer ring of the inner ring and the outer ring of the bearing. You may oppose the space between an inner peripheral surface and the axial direction of the said rotating shaft.

  According to this, it is easy to supply the lubricating oil flowing along the outer surface of the oil guide portion to the space between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring, and to lubricate the rolling elements arranged in the space. Easy to supply oil. For example, as compared with the case where the lubricating oil is supplied to the outer peripheral surface of the outer ring and then flows between the inner ring and the outer ring, the lubricating oil can be efficiently supplied to the space between the inner ring and the outer ring, Easy to lubricate rolling elements.

Further, in the electric supercharger, the oil guide portion may include an inclined portion that is inclined downward from the body portion side toward the tip edge along the axial direction of the rotation shaft.
According to this, the lubricating oil that flows on the outer surface of the oil guide portion along the axial direction of the rotating shaft is made to easily flow toward the bearing by utilizing the inclined portion, and the oil guide portion does not have the inclined portion. Compared with the case of extending along the direction, it becomes easier to supply the lubricating oil to the bearing.

Further, in the electric supercharger, the main body may have a dimension along the radial direction of the rotary shaft larger than a diameter of the rotary shaft.
According to this, the lubricating oil passed through the oil supply hole and dropped onto the coil end, and the lubricating oil supplied to the coil end passes through the gap between the conductors forming the coil end and drops toward the rotating shaft. . Lubricating oil that has dropped toward the rotating shaft falls on the main body located vertically above the rotating shaft and radially inside the rotating shaft from the outer peripheral surface of the coil end, and the lubricating oil that has fallen A part of the above falls from the outer side in the radial direction with respect to the rotation axis along the outer surface of the main body. Therefore, it is possible to suppress the amount of the lubricating oil that has passed through the coil end dropping on the rotating shaft, and reduce the rotational resistance of the rotating shaft due to the lubricating oil.

Further, in the electric supercharger, the oil guide portion may be semi-cylindrical, and the dimension of the oil guide portion along the radial direction of the rotary shaft may be larger than the diameter of the rotary shaft.
According to this, by making the oil guide part in a semi-cylindrical shape, the size of the oil guide part along the circumferential direction of the bearing can be increased as compared with the case where the oil guide part is an elongated plate shape. A shortage of lubricating oil that can be supplied to the bearing along the outer surface of the portion can be suppressed.

Further, in the electric supercharger, the oil guide portion may include a through hole that penetrates the oil guide portion in the thickness direction.
According to this, by providing the through hole in the oil guide portion, the lubricating oil that has dropped into the oil guide portion is prevented from flowing through the through hole with the lubricating oil flowing toward the bearing arranged on the side away from the tip end of the coil end. It can be divided into lubricating oil that passes and falls from the oil guide portion. Therefore, it is possible to suppress excessive supply of lubricating oil toward the bearing along the outer surface of the oil guide portion to the bearing.

  According to the present invention, the configuration for supplying the lubricating oil to the bearing can be simplified.

Sectional drawing which shows the electric supercharger of embodiment. The perspective view which shows an oil supply member. Sectional drawing which shows the state which attached the oil supply member to the stator. FIG. 3 is a partial cross-sectional perspective view showing the flow of lubricating oil. The partial cross section figure which shows the electric supercharger of another example.

  An embodiment in which the electric supercharger is embodied will be described below with reference to FIGS. 1 to 4. The electric supercharger of the present embodiment is installed in the engine room of an automobile and is used to compress and supply air as a fluid to the engine.

  As shown in FIG. 1, the housing 11 of the electric supercharger 10 includes a cylindrical motor housing 12, a disc-shaped first plate 13 connected to one axial end surface of the motor housing 12, and a motor housing 12. And a disk-shaped second plate 14 connected to the other end surface in the axial direction and a cover 14a attached to the second plate 14. Further, the housing 11 includes a compressor housing 15 connected to the side of the first plate 13 opposite to the motor housing 12. The motor housing 12, the first plate 13, the second plate 14, the cover 14a, and the compressor housing 15 are made of aluminum, for example.

  The first plate 13 includes a tubular first bearing portion 16. A bearing through hole 14h is formed in the second plate 14. The cylindrical second bearing case 17 is attached to the bearing through hole 14h. The cover 14a closes the opening of the bearing through hole 14h on the side opposite to the motor housing 12.

  The electric supercharger 10 includes a rotating shaft 20 rotatably supported by the housing 11. The rotary shaft 20 is inserted through the second bearing case 17, the motor housing 12, and the first plate 13. The rotary shaft 20 penetrates the first plate 13 and projects into the compressor housing 15. A shaft seal 13a is interposed between the rotary shaft 20 and the first plate 13.

  In the present embodiment, the side of the rotary shaft 20 projecting into the compressor housing 15 corresponds to one end side of the rotary shaft 20 in the axial direction, and the second bearing case 17 side of the rotary shaft 20 is the other end of the rotary shaft 20 in the axial direction. Corresponds to the side. An impeller 21 is fastened by a nut N to one end of the rotary shaft 20 in the axial direction.

  An electric motor 22 for rotating the rotary shaft 20 is housed in the motor housing 12 of the housing 11. The electric motor 22 is housed in a motor chamber 121, which is a space surrounded by the motor housing 12, the first plate 13, and the second plate 14.

  A discharge passage 54 for discharging the lubricating oil in the motor chamber 121 to the outside of the housing 11 is formed in the lower portion of the motor housing 12. The lubricating oil discharged to the outside of the housing 11 through the discharge passage 54 is collected as engine oil in the engine oil pan.

  The electric motor 22 includes a cylindrical stator 23 and a rotor 24 arranged inside the stator 23. A coil 25 is wound around the stator 23. The rotor 24 rotates integrally with the rotating shaft 20 by supplying a current to the coil 25.

  The stator 23 includes an annular stator core 23a. The stator core 23a has a cylindrical yoke 23b and a plurality of teeth 23c extending in the radial direction from the inner peripheral surface of the yoke 23b. As shown in FIG. 3, the plurality of teeth 23c are arranged at intervals in the circumferential direction of the stator core 23a. Collar portions 23d project from the tips of the teeth 23c toward the teeth 23c adjacent in the circumferential direction of the stator core 23a.

  In addition, as shown in FIG. 1, the coil 25 includes a first coil end 25e protruding from an end surface near the first plate 13 and an end surface near the second plate 14 on both axial end surfaces of the rotating shaft 20 in the stator core 23a. It has the 2nd coil end 25f projected from. The tip end surface 26 of the first coil end 25e in the protruding direction from the stator core 23a is separated from the first bearing portion 16 along the axial direction of the rotating shaft 20. Further, the tip end surface 27 of the second coil end 25f in the protruding direction from the stator core 23a is separated from the second bearing case 17 along the axial direction of the rotating shaft 20.

  The electric supercharger 10 includes a first bearing 31 that rotatably supports a portion of the rotating shaft 20 near the impeller 21. The first bearing 31 is housed in the first bearing portion 16. The first bearing 31 includes a first inner ring 31a fixed to the rotating shaft 20, a first outer ring 31b inserted into the first bearing portion 16, a first inner ring 31a and a first outer ring 31b. A plurality of first rolling elements 31c are arranged in the space between them.

  The electric supercharger 10 includes a second bearing 32 that rotatably supports a portion of the rotary shaft 20 farther from the impeller 21 than the first bearing 31 in the axial direction of the rotary shaft 20. Therefore, the rotating shaft 20 is rotatably supported by the housing 11 via the first bearing 31 and the second bearing 32. The second bearing 32 is housed in the second bearing case 17, and is arranged at the end of the second bearing case 17 opposite to the cover 14 a in the axial direction of the rotary shaft 20. The second bearing 32 is housed in the second bearing case 17.

  The second bearing 32 includes a second inner ring 32a fixed to the rotating shaft 20, a second outer ring 32b inserted in the second bearing case 17, a second inner ring 32a and a second outer ring 32b. A plurality of second rolling elements 32c are arranged in the space between them.

  In the second bearing case 17, a housing chamber 33 is provided between the second bearing 32 and the cover 14a in the axial direction of the rotary shaft 20. An annular washer 34 and a preload spring 35 are accommodated in the accommodation chamber 33. One end of the preload spring 35 contacts the cover 14a, and the other end of the preload spring 35 contacts the end face of the second outer ring 32b of the second bearing 32 via the washer 34. The preload spring 35 is arranged between the cover 14 a and the washer 34 while being compressed in the axial direction of the rotary shaft 20. Therefore, the cover 14 a holds the preload spring 35. Then, the preload spring 35 urges the second bearing 32 in the axial direction of the rotary shaft 20 by the force of returning to the original shape of the compressed preload spring 35.

  The compressor housing 15 includes an intake port 15a for intake of air (fresh air), an impeller chamber 15b communicating with the intake port 15a and accommodating an impeller 21, and a discharge chamber for ejecting air compressed by the impeller 21. 15 c, and a diffuser flow path 15 d that connects the impeller chamber 15 b and the discharge chamber 15 c.

  When the electric motor 22 is driven to rotate the rotary shaft 20, the impeller 21 rotates, and the centrifugal force of the rotating impeller 21 imparts velocity energy to the air sucked from the suction port 15a. The air that has been given high velocity due to the velocity energy is decelerated in the diffuser flow passage 15d provided at the outlet of the impeller chamber 15b, and the velocity energy of the air is converted into pressure energy. The high-pressure air is discharged from the discharge chamber 15c and supplied to an engine (not shown).

  An oil supply passage 44 extending in the axial direction of the rotary shaft 20 is provided in the upper part of the motor housing 12, which is the upper part of the housing 11. The oil supply passage 44 is formed by drilling from one end to the other end of the motor housing 12 along the axial direction of the rotary shaft 20. When casting the motor housing 12, the oil supply passage 44 may be formed by a mold. One end of the oil supply flow path 44 along the axial direction of the rotary shaft 20 is closed by the first plate 13. An annular seal member 13b is attached to one end surface of the motor housing 12 in the axial direction, and the seal member 13b surrounds an opening of the motor housing 12 on the one end side in the axial direction. The seal member 13b seals between the first plate 13 and the motor housing 12 and seals between the oil supply passage 44 and the first plate 13 on the one axial end side of the motor housing 12.

  The length of the oil supply passage 44 along the axial direction of the rotary shaft 20 is longer than the length of the electric motor 22 along the axial direction of the rotary shaft 20. One end in the lengthwise direction of the oil supply passage 44 is located closer to the first plate 13 than the tip surface 26 of the first coil end 25e, and the other end in the lengthwise direction of the oil supply passage 44 is the second coil. It is located closer to the second plate 14 than the front end surface 27 of the end 25f. Therefore, the oil supply flow path 44 overlaps the entire electric motor 22 in the vertical direction.

  A supply port 43 for supplying lubricating oil to the oil supply passage 44 is provided in the upper part of the motor housing 12, which is the upper part of the housing 11. A pump P for supplying lubricating oil is connected to the supply port 43. Then, by driving the pump P, the lubricating oil is supplied to the supply port 43 and the lubricating oil is supplied to the oil supply passage 44.

  A pair of oil supply holes 38 that connect the inside of the oil supply passage 44 and the inside of the housing 11 are provided on the upper side of the motor housing 12 that is the upper portion of the housing 11 and below the oil supply passage 44 in the vertical direction. It is provided. One oil supply hole 38 is located above the first coil end 25e, that is, above the vertical direction, and is arranged at a position overlapping the first coil end 25e in the radial direction of the rotating shaft 20. The other oil supply hole 38 is located above the second coil end 25f, that is, above the vertical direction, and is arranged at a position overlapping the second coil end 25f in the radial direction of the rotating shaft 20.

  A first oil supply member 50a is arranged between the inner peripheral surface of the upper part of the first coil end 25e and the upper peripheral surface of the rotary shaft 20. The first oil supply member 50a is located radially inward of the rotary shaft 20 with respect to the outer peripheral surface of the first coil end 25e and vertically upward with respect to the rotary shaft 20. A second oil supply member 50b is arranged between the inner peripheral surface of the upper part of the second coil end 25f and the upper peripheral surface of the rotary shaft 20. The second oil supply member 50b is located radially inward of the rotary shaft 20 with respect to the outer peripheral surface of the second coil end 25f and vertically upward with respect to the rotary shaft 20. Since the first oil supply member 50a and the second oil supply member 50b have the same configuration, they will be described with common member numbers.

  The first oil supply member 50a and the second oil supply member 50b have a semi-cylindrical base portion 51 and a semi-cylindrical shape extending from one axial end of the base portion 51 toward the bearings 31, 32. And an inclined portion 52 of. Further, the first oil supply member 50a and the second oil supply member 50b have a mounting portion 53 extending from the other axial end of the base portion 51 toward the center of the rotary shaft 20 in the axial direction. . The base portion 51, the inclined portion 52, and the mounting portion 53 are integrated. Each oil supply member 50a, 50b is made of resin having oil resistance and heat resistance. The heat resistance may be such that it does not deform even when exposed to heat of 120 to 130 ° C.

  As shown in FIG. 3, a virtual circle extending in the circumferential direction along the outer peripheral surface of the base portion 51 is referred to as a first virtual circle C1. A virtual circle that passes through the tips of the teeth 23c and extends in the circumferential direction of the stator 23 is referred to as a second virtual circle C2. The first virtual circle C1 and the second virtual circle C2 are concentric circles having the same center, and the diameter of the first virtual circle C1 is slightly larger than the diameter of the second virtual circle C2.

  As shown in FIG. 2, each mounting portion 53 of the oil supply members 50a and 50b is a plate-like member that projects in a slender manner from the base portion 51 along the axial direction of the base portion 51. Then, as shown in FIG. 3, when the oil supply members 50a and 50b are viewed from the axial direction, the outer surface of each mounting portion 53 has a curved shape along the first virtual circle C1 of the base portion 51. In addition, in this embodiment, the oil supply members 50a and 50b include five attachment portions 53. Of the five mounting portions 53, the mounting portions 53 located on both ends in the circumferential direction of the base portion 51 are located on the extension lines of the respective circumferential edges of the base portion 51. The remaining three mounting portions 53 are provided at equal intervals along the circumferential direction of the base 51. The dimension between the mounting portions 53 adjacent to each other in the circumferential direction of the base portion 51 is slightly larger than the dimension of the teeth 23c in the circumferential direction of the stator 23.

  The dimension of the mounting portion 53 along the circumferential direction of the base portion 51 is slightly shorter than the dimension at the position closest to the flange portion 23d among the dimensions between the teeth 23c adjacent to each other in the circumferential direction of the stator 23. Each mounting portion 53 is inserted between the teeth 23c adjacent to each other on the upper side in the vertical direction with respect to the rotating shaft 20. Each mounting portion 53 is supported from below by a collar portion 23d that is integral with a tooth 23c that sandwiches the mounting portion 53 in the circumferential direction of the stator 23, and the oil supply members 50a and 50b are integrated with the stator 23 by the support by the collar portion 23d. Is attached to.

  As shown in FIG. 1, due to the support by the collar portion 23d, a part of the base body portion 51 of the first oil supply member 50a rotates on the upper side in the vertical direction with respect to the rotation shaft 20 with the inner peripheral surface of the first coil end 25e. It is arranged between the peripheral surface of the shaft 20. In the first oil supply member 50a, a portion of the base body portion 51, which is disposed between the inner peripheral surface of the first coil end 25e and the peripheral surface of the rotating shaft 20 on the upper side in the vertical direction with respect to the rotating shaft 20, is the main body. It constitutes the part 55.

  Further, due to the support by the flange portion 23d, a part of the base body portion 51 of the second oil supply member 50b is vertically above the rotating shaft 20 in the inner peripheral surface of the second coil end 25f and the peripheral surface of the rotating shaft 20. It is located between and. In the second oil supply member 50b, a portion of the base body portion 51, which is disposed between the inner peripheral surface of the second coil end 25f and the peripheral surface of the rotary shaft 20 on the upper side in the vertical direction of the rotary shaft 20, is the main body. It constitutes the part 55.

  As shown in FIG. 3, the dimensions of the base portion 51 and the main body portion 55 along the radial direction of the rotary shaft 20 are larger than the diameter of the rotary shaft 20. Therefore, the main body 55 covers a part of the coil ends 25e and 25f along the axial direction of the rotary shaft 20 on the inner circumferential side of the upper part from the upper side over the entire radial direction of the rotary shaft 20.

  As shown in FIG. 2, the inclined portion 52 of the first oil supply member 50a is located radially inward of the outer peripheral surface of the first coil end 25e and vertically upward of the rotary shaft 20. The inclined portion 52 of the second oil supply member 50b is located radially inward of the outer peripheral surface of the second coil end 25f and vertically upward of the rotary shaft 20. The inclined portion 52 of each oil supply member 50a, 50b has a base end edge 52a that extends in a semicircular shape at the end edge near the base portion 51, and a tip edge that extends in an arc shape at the end edge near each bearing 31, 32. 52b. The dimension of the inclined portion 52 along the radial direction of the rotating shaft 20 is larger than the diameter of the rotating shaft 20. Therefore, each of the inclined portions 52 covers a part of the rotary shaft 20 along the axial direction from the upper side in the vertical direction along the axial direction of the rotary shaft 20 over the entire radial direction of the rotary shaft 20.

  As shown in FIG. 3, a virtual circle extending in the circumferential direction along the leading edge 52b is referred to as a third virtual circle C3. The third virtual circle C3 and the first virtual circle C1 are concentric circles having the same center, and the diameter of the third virtual circle C3 is smaller than the diameter of the first virtual circle C1. Further, the third virtual circle C3 is a concentric circle whose center is the same as that of the first bearing 31 and the second bearing 32. The diameter of the third virtual circle C3 is slightly larger than the outer diameters of the inner rings 31a and 32a of the bearings 31 and 32, and slightly smaller than the inner diameters of the outer rings 31b and 32b.

  As shown in FIG. 1, the inclined portion 52 of the first oil supply member 50 a and a part of the base body portion 51 are arranged along the axial direction of the rotating shaft 20 along with the tip end surface 26 of the first coil end 25 e and the first end portion 26. It is located between the bearing 31. The first oil supply member 50a is provided with an oil guide portion 56 at a portion located between the tip end surface 26 of the first coil end 25e and the first bearing 31 in the axial direction of the rotary shaft 20. The oil guide portion 56 is composed of the inclined portion 52 and a part of the base portion 51. The oil guide portion 56 of the first oil supply member 50a is disposed on the side away from the tip of the first coil end 25e in the axial direction of the rotary shaft 20 and the side away from the tip of the first coil end 25e. 1 extends from the main body 55 to the bearing 31 side. Therefore, the first oil supply member 50a has a main body portion 55 arranged radially inward of the outer peripheral surface of the first coil end 25e, and an oil guide portion 56 connected to the main body portion 55.

  The position of the tip of the first coil end 25e means that the position of the first coil end 25e closest to the first plate 13 along the axial direction of the rotating shaft 20 is, of course, It includes a position slightly closer to the first plate 13 and a position slightly closer to the stator core 23a than the closest position.

  In the present embodiment, a part of the base body portion 51 that constitutes the oil guide portion 56 of the first oil supply member 50a is a tip surface 26 of the base body portion 51 that is closest to the first plate 13 at the first coil end 25e. Is a portion slightly closer to the first plate 13. Therefore, the base end edge 52a of the inclined portion 52 is located slightly closer to the first plate 13 than the tip end surface 26 of the first coil end 25e.

  The oil guide portion 56 of the first oil supply member 50a is located between the end surface of the first bearing 31 and the tip surface 26 of the first coil end 25e in the axial direction of the rotary shaft 20 in the space inside the housing 11. A part of the rotary shaft 20 exposed in the space is covered over the entire axial direction.

  The tip edge 52b of the inclined portion 52, which is the tip edge of the oil guide portion 56 of the first oil supply member 50a, is located in the space between the outer peripheral surface of the first inner ring 31a and the inner peripheral surface of the first outer ring 31b. On the other hand, they are opposed to each other along the axial direction of the rotary shaft 20. Therefore, the tip end edge 52b of the oil guide portion 56 is located at the tip of the center point of the first rolling element 31c extending toward the first oil supply member 50a side along the axial direction of the rotary shaft 20.

  The inclined portion 52 of the second oil supply member 50b and a part of the base portion 51 are located between the distal end surface 27 of the second coil end 25f and the second bearing 32 along the axial direction of the rotating shaft 20. To do. The second oil supply member 50b includes an oil guide portion 56 at a portion located between the tip end surface 27 of the second coil end 25f and the second bearing 32 in the axial direction of the rotary shaft 20. The oil guide portion 56 is composed of the inclined portion 52 and a part of the base portion 51. The oil guide portion 56 of the second oil supply member 50b is disposed on the side away from the tip of the second coil end 25f from the position of the tip of the second coil end 25f in the axial direction of the rotary shaft 20. The second bearing 32 extends from the main body 55. Therefore, the second oil supply member 50b has a main body portion 55 arranged radially inward of the outer peripheral surface of the second coil end 25f, and an oil guide portion 56 connected to the main body portion 55.

  The position of the tip of the second coil end 25f means that the position of the second coil end 25f closest to the second plate 14 along the axial direction of the rotating shaft 20 is, as a matter of course, It includes a position slightly closer to the second plate 14 and a position slightly closer to the stator core 23a than the closest position.

  In the present embodiment, a part of the base body portion 51 that constitutes the oil guide portion 56 of the second oil supply member 50b is a portion of the base body portion 51 that is closest to the second plate 14 at the second coil end 25f and that is the front end surface 27. Is a portion slightly closer to the second plate 14. Therefore, the base end edge 52a of the inclined portion 52 is located slightly closer to the second plate 14 than the tip end surface 27 of the second coil end 25f.

  The oil guide portion 56 of the second oil supply member 50b is located between the end surface of the second bearing 32 and the tip surface 27 of the second coil end 25f in the axial direction of the rotary shaft 20 in the space inside the housing 11. A part of the rotary shaft 20 exposed in the space is covered over the entire axial direction.

  The tip edge 52b of the inclined portion 52, which is the tip edge of the oil guide portion 56 of the second oil supply member 50b, is located in the space between the outer peripheral surface of the second inner ring 32a and the inner peripheral surface of the second outer ring 32b. On the other hand, they are opposed to each other along the axial direction of the rotary shaft 20. Therefore, the tip edge 52b of the oil guide portion 56 is located at the tip of the center point of the second rolling element 32c extended to the second oil supply member 50b side along the axial direction of the rotary shaft 20.

  The inclined portion 52 of the oil guide portion 56 is provided with a plurality of through holes 52c penetrating the oil guide portion 56 in the thickness direction at equal intervals in the circumferential direction of the oil guide portion 56. Therefore, a part of the rotary shaft 20 is not covered with the oil guide portion 56 by the through hole 52c. The through hole 52c has a round hole shape. Then, by adjusting the size or number of the through holes 52c, it is possible to adjust the amount of lubricating oil flowing through the bearings 31 and 32 along the oil guide portion 56.

Next, the operation of this embodiment will be described.
As shown by the arrow Y in FIG. 1 or FIG. 4, in the electric supercharger 10, the pump P supplies the lubricating oil from the supply port 43 to the oil supply passage 44, and the lubrication supplied to the oil supply passage 44. The oil passes through the oil supply holes 38, drops to the first coil end 25e and the second coil end 25f, and is supplied to the coil ends 25e and 25f. Then, the coil ends 25e and 25f are cooled by the lubricating oil.

  The lubricating oil dropped on the coil ends 25e and 25f flows downward along the circumferential direction and the axial direction according to the shape of the outer peripheral surface of the coil ends 25e and 25f. In addition, the lubricating oil passes through the gap between the conductors forming the coil ends 25e and 25f, and flows below the coil ends 25e and 25f.

  Then, the lubricating oil that has flowed down from the outer peripheral surface of each coil end 25e, 25f to each tip surface 26, 27 side drops on the oil guide portion 56 of each oil supply member 50a, 50b. Since the oil guide portion 56 is arranged at the destination of the lubricating oil, the dropped lubricating oil flows along the outer surface of the oil guide portion 56 (a part of the main body portion 55 and the inclined portion 52). Of the lubricating oil flowing along the outer peripheral surface of the oil guide portion 56, the lubricating oil flows along the axial direction of the rotating shaft 20 and flows toward the bearings 31, 32 by utilizing the downward inclination of the inclined portion 52. Lubricating oil is supplied to the space between the outer peripheral surfaces of the inner rings 31a and 32a and the inner peripheral surfaces of the outer rings 31b and 32b. As a result, the lubricating oil is supplied to the rolling elements 31c and 32c, and the rolling elements 31c and 32c of the bearings 31 and 32 are lubricated.

  Further, a part of the lubricating oil that has dropped onto the oil guide portion 56 of each of the oil supply members 50a and 50b passes through the through hole 52c and drops from the inclined portion 52 of the oil guide portion 56. Therefore, the lubricating oil that has dropped to the oil guide portion 56 is divided into lubricating oil that travels through the inclined portion 52 toward the bearings 31 and 32 and lubricating oil that drops from the inclined portion 52, and falls on the oil guide portion 56. Not all of the lubricated oil is supplied to the bearings 31, 32.

  The lubricating oil that has passed between the conductors of the coil ends 25e and 25f drops onto the main body 55 of the oil supply members 50a and 50b. The lubricating oil that has dropped onto the main body 55 splits along the circumferential direction along the outer peripheral surface of the main body 55, and falls below the main body 55 from the radially outer side of the rotary shaft 20. Then, the lubricating oil that has passed through the coil ends 25e and 25f and dropped below the coil 25, the lubricating oil that has dropped along the circumferential surface of the oil guide portion 56, and the lubricating oil that has passed through the through hole 52c. Flows into the discharge passage 54 and is discharged to the outside of the housing 11 through the discharge passage 54. The lubricating oil discharged to the outside of the housing 11 is collected as engine oil in an oil pan of the engine.

According to the above embodiment, the following effects can be obtained.
(1) The first and second oil supply members 50a and 50b are arranged between the inner peripheral surfaces of the coil ends 25e and 25f and the peripheral surface of the rotary shaft 20 on the vertically upper side of the rotary shaft 20. It has a main body 55. In addition, the first and second oil supply members 50a and 50b are provided with bearings 31 and 32 arranged on the side away from the positions of the tip ends of the coil ends 25e and 25f, respectively. Has an oil guide portion 56 extending from the main body portion 55. Therefore, the lubricating oil dropped from the coil ends 25e and 25f can be supplied to the bearings 31 and 32 by flowing along the axial direction of the rotating shaft 20 by the oil guide portion 56. Therefore, the lubricating oil can be supplied to the bearings 31 and 32 only by installing the oil supply members 50a and 50b in the housing 11. Therefore, in order to supply the lubricating oil to the bearings 31 and 32, it is not necessary to process the housing 11 such as the first plate 13 and the motor housing 12 to form the flow path, and to supply the lubricating oil to the bearings 31 and 32. The configuration for doing so can be simplified.

  (2) Lubricating oil is almost always supplied for cooling the coil ends 25e and 25f. Therefore, the lubricating oil flowing down from the coil ends 25e and 25f is almost always supplied to the oil guide portion 56, and the lubricating oil can be supplied to the bearings 31 and 32 almost always. Therefore, it is possible to suppress the temperature rise of the bearings 31 and 32 and continuously operate the electric supercharger 10.

  (3) The tip edge 52b of the inclined portion 52 that constitutes the oil guide portion 56 rotates with respect to the space between the outer peripheral surfaces of the inner rings 31a and 32a of the bearings 31 and 32 and the inner peripheral surfaces of the outer rings 31b and 32b. The shaft 20 faces the axial direction. Therefore, the lubricating oil flowing along the outer surface of the inclined portion 52 of the oil guide portion 56 can be directly supplied to the space between the outer peripheral surfaces of the inner rings 31a, 32a and the inner peripheral surfaces of the outer rings 31b, 32b, and the rolling elements 31c. , 32c is easy to supply. For example, as compared with the case where the lubricating oil is supplied to the outer peripheral surfaces of the outer rings 31b and 32b and then flows between the inner rings 31a and 32a and the outer rings 31b and 32b, the inner rings 31a and 32a and the outer rings 31b and 32b are Lubricating oil can be efficiently supplied in the meantime.

  (4) The inclined portion 52 that constitutes the oil guide portion 56 is inclined downward from the base edge 52a toward the tip edge 52b. Therefore, the lubricating oil flowing in the oil guide portion 56 along the axial direction of the rotary shaft 20 can be made to flow down toward the tip edge 52b of the oil guide portion 56 by the inclined portion 52. As a result, the lubricating oil can be efficiently supplied to the space between the outer peripheral surfaces of the inner rings 31a and 32a and the inner peripheral surfaces of the outer rings 31b and 32b of the bearings 31 and 32 with the front edges 52b facing each other.

  (5) The size of the main body 55 in the radial direction of the rotary shaft 20 is larger than the diameter of the rotary shaft 20. Therefore, the lubricating oil that has passed through the coil ends 25e and 25f and dropped onto the main body portion 55 can flow along the outer surface of the main body portion 55 below the main body portion 55 from the radial outside of the rotary shaft 20. it can. Therefore, the amount of the lubricating oil that has passed through the coil ends 25e and 25f falling on the rotating shaft 20 can be suppressed, and the rotational resistance of the rotating shaft 20 due to the lubricating oil can be reduced. As a result, the power consumption of the electric motor 22 can be reduced as compared with the case where the main body 55 is not provided.

  (6) The oil guide portion 56 has a semi-cylindrical shape, and the dimension of the oil guide portion 56 along the radial direction of the rotary shaft 20 is larger than the diameter of the rotary shaft 20. Therefore, for example, the dimension of the oil guide portion 56 along the circumferential direction of each bearing 31, 32 can be increased as compared with the case where the entire oil guide portion 56 is an elongated horizontal plate shape, and the outer peripheral surface of the oil guide portion 56 can be increased. It is possible to suppress the shortage of the lubricating oil that can be supplied to the bearings 31 and 32 along.

  (7) Lubricating oil that has dropped into the oil guiding portion 56 due to the through hole 52c of the inclined portion 52 that constitutes the oil guiding portion 56, lubricating oil that flows into the bearings 31 and 32, and lubricating oil that falls from the oil guiding portion 56. Can be divided into Therefore, it is possible to prevent the lubricating oil from being excessively supplied to the bearings 31 and 32.

  (8) Each of the oil supply members 50a and 50b includes a plurality of mounting portions 53, and each mounting portion 53 is inserted between the teeth 23c adjacent to each other in the circumferential direction in the stator 23, and the collar portion 23d integrated with each tooth 23c. It is supported from below by. Therefore, the oil supply members 50a and 50b are integrally attached to the stator 23 and can be prevented from falling onto the rotary shaft 20 by being supported by the collar portion 23d.

The above embodiment may be modified as follows.
As shown in FIG. 5, the oil supply member 60 may be extended from the first bearing portion 16 and the oil supply member 60 may be extended from the second bearing case 17. Each oil supply member 60 includes an oil guide portion 61 and a body portion 63. Each main body portion 63 is arranged vertically above the rotary shaft 20 and radially inside the rotary shaft 20 with respect to the outer peripheral surface of each coil end 25e, 25f. Further, each oil guide portion 61 is provided with each bearing 31, which is arranged on the side away from the tip end of each coil end 25e, 25f in the axial direction of the rotary shaft 20 and the tip end of each coil end 25e, 25f. It extends from the main body portion 63 to the 32 side. Each oil guide portion 61 covers the rotary shaft 20 from the upper side in the vertical direction along the axial direction. In this embodiment, the oil guide portion 61 has a semi-cylindrical shape extending in the circumferential direction of each outer ring 31b, 32b.

Even with such a configuration, the same effects as (1), (2), (5), (6) and (7) of the embodiment can be obtained.
The through hole 52c of the oil guide portions 56, 61 may be omitted.

The through holes 52c of the oil guide portions 56 and 61 do not have to be round holes, and may be, for example, long holes or square holes.
The oil guide portions 56 and 61 do not have to be semi-cylindrical, and for example, the length in the circumferential direction may be shorter or longer than the semi-cylindrical shape.

The oil guide portions 56 and 61 do not have to have a curved shape, and may have, for example, a mountain shape or a flat shape when viewed in the axial direction of the rotating shaft 20.
The body portions 55 and 63 do not have to have a semi-cylindrical shape. For example, the length in the circumferential direction may be shorter or longer than the semi-cylindrical shape.

The body portions 55 and 63 do not have to have a curved shape, and may have, for example, a mountain shape or a flat shape when viewed in the axial direction of the rotary shaft 20.
The mounting portion 53 may be omitted, and in this case, in each oil supply member 50a, 50b, the base portion 51 (main body portion 55) is adhered to the front end surface of the collar portion 23d and the upper portion of each coil end 25e, 25f. The base portion 51 (main body portion 55) may be directly attached and attached to the inner peripheral surface of each coil end 25e, 25f.

The number of mounting portions 53 may be less than 5, or more than 5.
The position of the tip end of each coil end 25e, 25f may be a position that coincides with the tip end face 26, 27 of each coil end 25e, 25f in the axial direction of the rotary shaft 20, or may be a position slightly closer to the stator core 23a. Good.

  The tip edge 52b of the inclined portion 52 forming the oil guide portion 56 does not have to face the space between the outer peripheral surfaces of the inner rings 31a and 32a and the inner peripheral surfaces of the outer rings 31b and 32b. For example, the tip edge 52b of the inclined portion 52 may be opposed to the outer peripheral surfaces of the inner rings 31a and 32a, or may be opposed to the inner peripheral surfaces of the outer rings 31b and 32b.

  The shape of the oil guide portion 56 of each oil supply member 50a, 50b is inclined downward from each of the end faces 26, 27 of the coil ends 25e, 25f toward the bearing 31, 32 from a position closer to the outer peripheral surface. Good. In this case, a part of the base portion 51 is inserted into the tip surfaces 26, 27 of the coil ends 25e, 25f to attach the oil supply members 50a, 50b to the coil ends 25e, 25f.

  In the housing 11, the motor housing 12 may have a bottomed tubular shape. In this case, the housing 11 includes a disk-shaped plate 13 connected to one axial end surface of the motor housing 12, and the motor housing 12. A disk-shaped cover 14a connected to the bottom wall at the other axial end.

  The oil supply passage 44 on the upper part of the housing 11 may be omitted. In this case, the pump P may be directly connected to the oil supply hole 38 provided in the upper part of the housing 11, and the lubricating oil may be directly supplied to the oil supply hole 38 by the pump P.

  At least one of the first bearing 31 and the second bearing 32 may be a sliding bearing.

  10 ... Electric supercharger, 11 ... Housing, 20 ... Rotating shaft, 21 ... Impeller, 22 ... Electric motor, 23 ... Stator, 23a ... Stator core, 25e ... 1st coil end, 25f ... 2nd coil end, 26, 27 ... Tip surface, 31 ... First bearing, 31a ... First inner ring, 31b ... First outer ring, 31c ... First rolling element, 32 ... Second bearing, 32a ... Second inner ring, 32b ... 2 outer ring, 32c ... 2nd rolling element, 38 ... Oil supply hole, 44 ... Oil supply flow path, 50a ... 1st oil supply member, 50b ... 2nd oil supply member, 52 ... Inclined part, 52b ... Tip edge, 52c ... Through hole, 55, 63 ... Main body section, 56, 61 ... Oil guide section, 60 ... Oil supply member.

Claims (6)

Housing,
A rotating shaft rotatably supported on the housing via a bearing,
An impeller connected to one end side in the axial direction of the rotating shaft,
An electric motor housed in the housing and rotating the rotating shaft,
The electric motor is an electric supercharger including a stator having a stator core, and coil ends protruding from both end surfaces of the stator core located in the axial direction of the rotating shaft,
An oil supply passage extending in the axial direction of the rotating shaft is provided in the upper part of the housing, and an oil supply hole communicating with the oil supply passage and located above the coil end in the vertical direction is provided,
A main body portion that is arranged radially inward of the outer peripheral surface of the coil end at a position vertically above the rotating shaft;
And an oil supply member having an oil guide portion extending from the main body portion on the bearing side arranged on the side away from the tip end portion of the coil end from the position of the tip end portion of the coil end in the axial direction of the rotating shaft. An electric supercharger characterized by that.   The bearing has an inner ring fixed to the rotating shaft, an outer ring arranged outside the inner ring, and a rolling element arranged between the inner ring and the outer ring, and the oil guide portion. Has a tip edge near the bearing arranged on the side away from the tip of the coil end, and the tip edge is a space between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring in the bearing. On the other hand, the electric supercharger according to claim 1, which faces the axial direction of the rotary shaft.   The electric supercharger according to claim 2, wherein the oil guide portion has an inclined portion that is inclined downward from the main body portion side toward the tip edge along the axial direction of the rotating shaft.   The electric supercharger according to any one of claims 1 to 3, wherein a dimension of the main body portion along a radial direction of the rotary shaft is larger than a diameter of the rotary shaft.   The said oil guide part is a semi-cylindrical shape, and the dimension of the said oil guide part along the radial direction of the said rotary shaft is larger than the diameter of the said rotary shaft. Electric supercharger.   The electric supercharger according to any one of claims 1 to 5, wherein the oil guide portion includes a through hole that penetrates the oil guide portion in a thickness direction.